This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Study to Investigate the Association of Real-world Sensor-derived Biometric Data With Clinical Parameters and Patient-reported Outcomes for Monitoring Disease Activity in Patients With COPD (NCT05655832), a non-randomized na study. The primary outcome is Chronic Obstructive Pulmonary Disease (COPD) Exacerbations of Sensor-collected Parameters During Observation Period - Physical Activity.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05655832 |
| Phase | NA |
| Condition | Pulmonary Disease, Chronic Obstructive |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 77 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Merck Healthcare KGaA, Darmstadt, Germany, an affiliate of Merck KGaA, Darmstadt, Germany |
| Results posted | Yes |
2. Clinical Question
Population
The main population was a cohort of participants with chronic obstructive pulmonary disease (COPD) who met the study’s inclusion criteria and none of its exclusion criteria. The registry record says that this cohort was followed for 3 months. A separate calibration cohort included participants without COPD and was followed for 2 weeks. The record defines the analyzed population at a given time point as participants evaluable at that time point; it does not report the number evaluable for each endpoint or time point.
Intervention
The study used a Vivalink wearable device to collect real-world biometric data. The device was the measurement tool, not a treatment assignment. The registry describes sensor-derived measures and includes an activity flag based on a predefined threshold for adult movement, as well as a method for identifying periodic movement relevant to stair climbing.
Comparator
The study was non-randomized and had no masking. The non-COPD calibration cohort is not a like-for-like control group for the COPD cohort. It can provide a separate calibration context, but the registry record does not describe a randomized or otherwise comparable control condition. The study design therefore does not support reading a difference between cohorts as a causal effect of the device or of a treatment.
Primary question
The primary endpoint concerns mean physical activity, measured in minutes, using sensor-collected parameters in the COPD cohort. The recorded timeframe is Day 0 (Baseline) and Day 8 to Day 14. More broadly, the study asks whether real-world sensor-derived biometric data are associated with clinical parameters and patient-reported outcomes, with the stated aim of monitoring disease activity and predicting exacerbations. Numerical endpoint results and reported correlation estimates are not reported in the registry record.
3. Trial Design
This is a completed, multicenter, prospective cohort study, registered as NCT05655832. The registry lists a start date of 2022-12-05 and a primary completion date of 2023-10-31. Enrollment is listed as 77. The study has no trial phase, is non-randomized, has no masking, and uses a parallel model. These design features describe how the cohorts were organized; they do not establish that the cohorts were assigned or matched to make a causal comparison.
The main cohort comprised participants with COPD, followed for 3 months. A separate calibration cohort comprised participants without COPD and was followed for 2 weeks. The device intervention listed in the record is the Vivalink wearable device. In this observational setting, the device collects measurements; the record does not describe assignment to a therapeutic intervention. Arm-specific descriptions are not reported in the registry record.
The study’s stated purpose is to investigate associations between real-world sensor-derived biometric data and clinical parameters or patient-reported outcomes. Its stated monitoring aim includes disease activity and prediction of exacerbations. The primary outcome is described as mean physical activity in minutes, with observations at Day 0 (Baseline) and Day 8 to Day 14. Secondary outcomes include correlations with the COPD Assessment Test (CAT), lung function measures (FEV1, FVC, and FEV1/FVC), and specified laboratory measures at baseline and study end.
The record lists 37 outcome measures, but no analysis entries. It does not report a randomized comparison, a detailed statistical analysis plan, or numerical primary endpoint results. The non-COPD calibration cohort should therefore be interpreted as a distinct cohort, not as an equivalent comparator for estimating a COPD-specific causal effect.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Calibration Cohort | COPD Cohort |
|---|---|---|
| STARTED | 10 | 67 |
| COMPLETED | 10 | 64 |
| NOT COMPLETED | 0 | 3 |
Reasons for not completing this period:
| Reason | Calibration Cohort | COPD Cohort |
|---|---|---|
| Not mentioned | 0 | 1 |
| Withdrawal by Subject | 0 | 1 |
| Protocol non-compliance | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: COPD cohort consisted of all participants with COPD fulfilling all of the inclusion criteria and none of the exclusion criteria. Here, "Number analyzed" signifies those participants who were evaluable at specified time point
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Intention-To-Treat (ITT) population consisted of the following analysis sets: COPD analysis set: all eligible participants with COPD \& Calibration analysis set: all eligible participants with non-COPD
| Characteristic | Unit | Calibration Cohort | COPD Cohort | Total |
|---|---|---|---|---|
| Participants analysed | 10 | 67 | 77 | |
| Age, Continuous | years | 52 (43.75 to 58.75) | 67 (61 to 71.5) | 66 (59 to 71) |
| Sex: Female, Male: Female | Participants | 8 | 37 | 45 |
| Sex: Female, Male: Male | Participants | 2 | 30 | 32 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 10 | 67 | 77 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Chronic Obstructive Pulmonary Disease (COPD) Exacerbations of Sensor-collected Parameters During Observation Period - Physical Activity, measured over Day 0(Baseline) and Day 8 to Day 14.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | minutes |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is described as mean physical activity, measured in minutes, using sensor-collected parameters during the observation period. The listed timeframe is Day 0 (Baseline) and Day 8 to Day 14. The record explains that an activity flag is extracted from the wearable’s accelerometer using a predefined threshold for adult movement. For stair climbing, periodic movement is identified through frequency analysis over specified time windows, with a ratio to the total spectrum used to indicate periodic activity above a threshold.
Physical activity is relevant to the study’s stated goal because it is a sensor-derived behavior that may be examined alongside clinical measures and participants’ reported health status. In general, wearable measurements can capture activity outside a clinic visit, while clinical tests and questionnaires provide different kinds of information. Whether those measures are associated, and how strong or precise any association is, must be assessed from the actual estimates and their uncertainty; these numerical results are not reported in the registry record.
The endpoint title refers to COPD exacerbations of sensor-collected parameters, but the primary measure specified in the record is physical activity. The record does not provide a numerical mean, standard deviation, change estimate, or correlation for this endpoint. It also does not explain the operational definition of an exacerbation within the primary endpoint. The listed measure should therefore be read as a sensor-derived physical-activity outcome, not as a reported count or rate of exacerbations.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the study’s intended question and the primary outcome, but it does not report the numerical results needed to judge the observed level or pattern of physical activity. No endpoint mean, standard deviation, estimated change, confidence interval, or p-value is reported in the record. A direction or magnitude of association cannot be inferred from the study objective or from the endpoint description alone.
The primary outcome is a continuous measure summarized as a mean with standard deviation. In general, a mean describes the center of observed measurements, while a standard deviation describes their spread. Neither can be interpreted without the corresponding reported values and the number of participants contributing at the relevant time point. The registry defines “Number analyzed” as participants evaluable at a specified time point, but does not report time-specific analyzed counts in the registry record for this study.
The broader objective concerns associations between sensor data and clinical parameters or patient-reported outcomes. The secondary outcome descriptions name CAT, FEV1, FVC, FEV1/FVC, white blood cell count, erythrocyte count, partial pressure of oxygen (pO2), and partial pressure of carbon dioxide (pCO2). Naming these outcomes does not establish that any association was present. Numerical correlation estimates and their uncertainty are not reported in the registry record.
The cohort design also matters for interpretation. Participants were not randomized, and the calibration cohort without COPD is not a like-for-like control comparison. Any observed relationship would be an association in the studied setting, not evidence that wearing the device caused a change in activity or clinical status. Potential differences between cohorts cannot be attributed to a particular cause from the design information alone.
The registry lists enrollment of 77, while the adverse-event group summaries list 67 at risk in each cohort. These figures refer to different record entries and should not be combined or treated as interchangeable analysis denominators. The record does not explain the relationship between enrollment and the adverse-event denominators. Nor does it report the number evaluable for the primary endpoint.
Consequently, the statistical interpretation is limited to what the record documents: the intended observational question, the endpoint definition, and the study structure. The posted data described in the record do not support a conclusion about the size, precision, or statistical significance of an endpoint result. A lack of a reported estimate is not evidence that an association was absent.
9. Statistical Methods Explained
What does a mean with standard deviation describe?
The primary outcome is specified as a mean of a continuous measure, with standard deviation as its dispersion measure. In general, the mean summarizes the average observed measurement among the participants included in that analysis. The standard deviation describes how spread out individual measurements are around that average. It is not the same as a confidence interval: a confidence interval describes uncertainty around an estimate, while a standard deviation describes variation among observations.
Neither summary can be interpreted in isolation. The mean needs its measurement unit and time point, and the standard deviation needs to be understood in relation to the measurement’s scale and distribution. The record gives the unit as minutes and lists Day 0 (Baseline) and Day 8 to Day 14. Numerical means, standard deviations, and confidence intervals are not reported in the registry record, so the outcome’s observed level and precision cannot be assessed.
What would a correlation estimate mean?
The study’s broader aim concerns associations between sensor data and clinical parameters or patient-reported outcomes. In general, a correlation describes how two measurements vary together. It does not establish that one measurement causes the other to change. Interpretation also depends on the correlation method, the observations included, the estimate’s uncertainty, and the measurements’ timing. Those analysis details and numerical correlation estimates are not reported in the registry record.
The named secondary measures include CAT, lung function measures, and laboratory values at baseline and study end. These measures represent distinct types of information and may have different scales. A correlation with a questionnaire score is not interchangeable with a correlation with a lung-function measurement. The record lists these outcomes but does not provide estimates that would allow their magnitude or precision to be compared.
Why do the cohort design and measurement process matter?
This is a prospective, non-randomized cohort study. In general, prospective collection can align measurement timing with a planned observation period, but it does not remove confounding or make cohort comparisons causal. The study lists a COPD cohort and a non-COPD calibration cohort, with different follow-up durations. The record does not describe the calibration cohort as a control condition or explain a method for adjusting comparisons between cohorts.
The endpoint depends on sensor processing. The record describes an accelerometer activity flag using a predefined movement threshold and a frequency-based method for periodic stair-climbing movement. These definitions help explain what the device-derived signal represents, but the record does not report validation results, sensor wear completeness, or how gaps in measurement were handled. Those details are important in general because an algorithmic activity measure can depend on data capture and processing choices.
What can be inferred from the listed analyses?
The record lists 37 outcome measures and no analysis entries. This means the registry information described in the record does not supply numerical analyses for interpreting the primary or secondary outcomes. It does not establish that no analyses were conducted outside the registry record; their results are simply not reported in the registry record. No statistical test, model, covariate adjustment, or confidence-interval procedure is described in the registry record for this study.
In general, model choice should reflect the measurement scale, study design, and data structure. Repeated observations from the same participant are related, so a method that accounts for that dependence may be appropriate when analyzing repeated measures. A simple correlation or comparison can fail to reflect that structure if it treats observations as independent. Whether such methods were used is not reported in the registry record.
How should planning illustrations be interpreted?
In general, a sample-size illustration based on an observed effect is a planning exercise, not a statement of observed power. The record’s stated illustration assumptions are a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect defined as a stated fraction of the observed effect. For time-to-event outcomes, the described planning quantity is total events; for other outcomes, it is participants per arm. Those assumptions do not establish that the study was designed using those calculations. The registry record does not report its own sample-size justification or design rationale, and numerical planning results are not reported in the registry record for this study.
Because the outcome estimates and analysis details are not reported, there is no basis to recalculate an effect or its uncertainty. A planning illustration cannot substitute for the observed endpoint estimate, and it cannot show whether a study result was statistically significant or clinically important.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 37 outcome measures, including the primary physical-activity outcome and secondary measures involving CAT, lung function, and laboratory values. When a study examines many outcomes or relationships, the chance of obtaining at least one apparently notable result can increase. In general, multiplicity procedures can address this issue, but the appropriate approach depends on which outcomes were prespecified as primary, how they were grouped, and the intended interpretation.
The registry record does not report a multiplicity adjustment, a hierarchy of hypotheses, or a detailed statistical analysis plan. It also lists no analysis entries. This does not show that no analysis or multiplicity handling occurred outside the registry; the method is simply not reported in the registry record. With no reported estimates or analysis procedures, the results cannot be assessed for selective emphasis across outcomes.
Missing-data handling is also not reported in the registry record. The primary outcome description defines the number analyzed as participants evaluable at the specified time point. That definition clarifies that the analysis population may depend on evaluability, but it does not explain how missing sensor data, incomplete follow-up, or unavailable clinical assessments were handled. The record does not report imputation, exclusion rules beyond the stated eligibility definition, or sensitivity analyses for missing observations.
The record describes the COPD cohort as participants fulfilling all inclusion criteria and none of the exclusion criteria. It does not provide endpoint-specific analysis counts or explain how the analysis population differed across outcomes and time points. Therefore, the amount and potential impact of missing data cannot be determined from the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Calibration Cohort | 0 | 67 | 0.0% |
| COPD Cohort | 3 | 67 | 4.5% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Calibration Cohort | 0 of 67 |
| COPD Cohort | 0 of 67 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Calibration Cohort | 0 of 67 |
| COPD Cohort | 3 of 67 |
Most frequent serious adverse event terms
| Event term | Organ system | Calibration Cohort | COPD Cohort |
|---|---|---|---|
| Chronic obstructive pulmonary disease | Respiratory, thoracic and mediastinal disorders | 0 of 67 | 2 of 67 |
| Deep Vein Thrombosis | Vascular disorders | 0 of 67 | 1 of 67 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Calibration Cohort | COPD Cohort |
|---|---|---|---|
| Chronic obstructive pulmonary disease | Respiratory, thoracic and mediastinal disorders | 0 of 67 | 2 of 67 |
| Upper respiratory tract infection | Infections and infestations | 0 of 67 | 1 of 67 |
Serious events with the highest arm-level rate: chronic obstructive pulmonary disease (3.0%), deep vein thrombosis (1.5%).
The registry’s adverse-event summaries list a calibration cohort and a COPD cohort. Each is shown with 67 participants at risk for serious adverse events and 67 at risk for other adverse events. Serious adverse events affected 0 participants in the calibration cohort and 3 in the COPD cohort. Other adverse events affected 0 participants in the calibration cohort and 3 in the COPD cohort. Deaths are listed as 0 in both cohorts.
The serious-event terms listed include chronic obstructive pulmonary disease at 3.0% and deep vein thrombosis at 1.5%. These percentages are registry entries; the record does not explain their denominator or provide enough detail to reconcile them with the participant-level summaries. They should not be converted into counts or treated as rates without that information.
These summaries describe events recorded during the study; they do not establish that the wearable device caused an event. The registry record does not report an attribution assessment, event timing, severity details beyond the serious-event classification, or a comparison adjusted for differences between cohorts. Because the study is non-randomized and the cohorts are not like-for-like controls, their event summaries should be read descriptively, not as a comparative estimate of risk.
12. What the Result Does, and Does Not, Mean
The study addresses a practical measurement question: whether data collected by a wearable device are associated with clinical parameters and patient-reported outcomes in participants with COPD. The stated aim also includes monitoring disease activity and predicting exacerbations. The primary outcome is mean sensor-derived physical activity in minutes, with the recorded timeframe at Day 0 (Baseline) and Day 8 to Day 14.
Those aims are not themselves findings. The registry record does not report the primary endpoint’s numerical mean or standard deviation, an estimated change, a correlation estimate, or uncertainty around an estimate. It therefore cannot show the magnitude or precision of an observed association. The absence of a reported result should not be interpreted as a finding of no association.
Even if associations were reported, an observational cohort design would not by itself demonstrate that device use causes changes in activity or health. Participants were not randomized, and the non-COPD calibration cohort is not a like-for-like control group. An association between a sensor measure and a clinical or patient-reported measure could reflect multiple factors; the registry record does not report an adjustment strategy that would resolve those concerns.
The device data also represent measurements created through sensor processing. The record describes an activity threshold and a method for identifying periodic movement, but does not report sensor validation, wear completeness, or data-quality results. Those details would help readers judge what the biometric measures capture and how representative the recorded data are.
The study can therefore be understood as a prospective effort to examine wearable measurements alongside established clinical and patient-reported measures. The record provides its design, intended outcomes, and some safety summaries, but not the numerical outcome evidence needed to assess whether the proposed monitoring relationships were observed or how reliably they were estimated.
13. Why This Trial Matters Statistically
Wearable measurements raise statistical questions that differ from questions based only on measurements collected during clinical visits. A device can produce observations across ordinary activity, but those observations depend on wear, data capture, and processing rules. This study’s description makes that issue concrete by defining an accelerometer activity flag and a frequency-based method for periodic stair-climbing movement.
The intended associations also span different kinds of measures: sensor-derived activity, questionnaire responses, lung function, and laboratory values. Statistically, these outcomes do not automatically share the same scale, timing, or interpretation. A relationship between two measures needs to be reported with an estimate and uncertainty, and should not be treated as causal merely because measurements are collected prospectively.
The non-randomized cohort structure is important to the interpretation. The COPD cohort and non-COPD calibration cohort have different purposes and follow-up durations, and the registry does not describe them as equivalent comparison groups. Recognizing that distinction helps avoid treating a calibration cohort as though it were a randomized control arm.
The record also illustrates why registration details and numerical results are both needed. It identifies a primary endpoint, 37 outcome measures, and a population definition, but lists no analysis entries and does not report numerical endpoint results. Without estimates, analysis methods, and endpoint-specific denominators, readers cannot evaluate magnitude, precision, missingness, or the handling of multiple outcomes. The statistical importance of the study lies in the measurement and association questions it poses; the record alone does not establish the performance or usefulness of the sensor measures.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for statistical interpretation is that numerical results for the primary endpoint are not reported in the registry record. The mean and standard deviation are specified as the summary measures, but their values are not given. Numerical results for the named clinical and patient-reported associations are also not reported. As a result, readers cannot assess effect size, precision, or whether estimates are compatible with a range of possible relationships.
The registry lists 37 outcome measures and no analysis entries. It does not report the statistical analysis plan, the methods used for correlation or repeated measurements, or whether multiplicity was addressed. The record also does not describe missing-data handling, sensor wear completeness, validation of the processed measures, or endpoint-specific analysis counts.
The study is non-randomized and unmasked, and the non-COPD calibration cohort is not a like-for-like control comparison. This limits causal interpretation and makes direct cohort contrasts difficult to interpret. The record does not provide matching or adjustment details that would clarify how differences between cohorts were handled.
Enrollment is listed as 77, while the adverse-event summaries list 67 at risk in each cohort. The registry record does not explain the relationship between these entries, and no endpoint-specific denominator is reported in the registry record for this study. They should not be reconciled by assumption. The record also does not report the protocol rationale or sample-size justification. These omissions constrain interpretation of the design and results, rather than demonstrating that a particular analysis was inappropriate.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study to Investigate the Association of Real-world Sensor-derived Biometric Data With Clinical Parameters and Patient-reported Outcomes for Monitoring Disease Activity in Patients With COPD — NCT05655832.
- Registry record last updated 2026-01-15; status last verified 2025-12.
- Results first posted 2026-01-15.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT05655832 is a completed, multicenter, prospective, non-randomized cohort study of wearable sensor-derived biometric data in COPD. The registry lists enrollment of 77, a start date of 2022-12-05, and a primary completion date of 2023-10-31. It describes a COPD cohort followed for 3 months and a non-COPD calibration cohort followed for 2 weeks. The listed device is the Vivalink wearable device.
The primary outcome is mean physical activity in minutes, with observations specified at Day 0 (Baseline) and Day 8 to Day 14. Secondary outcomes include associations with CAT, lung function, and laboratory measures. The record lists 37 outcome measures and no analysis entries. Numerical primary and secondary outcome results are not reported in the registry record.
Safety summaries list 3 participants with serious adverse events in the COPD cohort and 0 in the calibration cohort; deaths are listed as 0 in both. The study’s observational design and the distinct roles of its cohorts limit causal interpretation.